The X-Men movies break their own rules.

Having seen all the X-Men movies, as well as the two Wolverine spinoff flicks, I was encouraged by the reviews that said that “X-Men: Days of Future Past” would finally clean up the mess left by the dreadful “X-Men 3: The Last Stand.”

This film series has been plagued by plot holes, and many wish that the third movie had simply never happened. “Days of Future Past,” with its time-traveling plot, essentially grants that wish by altering the past to create a new future that lifts the franchise out of the corner into which it had painted itself.

Now don’t get me wrong. I quite enjoyed “Days of Future Past,” and I consider it to be the best X-Men movie to date. The scenes with Quicksilver, the mutant with a need for speed, may well be the most entertaining moments of superhero cinema ever filmed. Taken as a standalone piece of entertainment, the movie is superb.

But when considered part of a larger whole, “Days Of Future Past” only served to exacerbate the X-movie continuity problems it was ostensibly designed to fix.

Let’s start with the problem of Professor Charles Xavier, as portrayed by Patrick Stewart. This character died about halfway through the third movie. His body was blasted into a million pieces, and it was kind of a big deal. Yet at the beginning of this latest outing, Patrick Stewart’s Xavier is back, front and center, battling the bad guys without missing a beat. Nothing in the “Days of Future Past” time-shifting narrative allows for this possibility, and the professor’s passing never even gets a passing mention.

I can’t imagine I’m the only one who was bothered by this.

When I’ve raised this issue, some are eager to point out that Professor X did, in fact, return from the dead in a post-credits scene at the end of “The Last Stand.” Well, yes. But he did so by transferring his consciousness into someone else’s brain-dead body — someone who presumably didn’t look exactly like Patrick Stewart. In addition, Professor X is still in a wheelchair at the outset of “Days of Future Past.” So even if this body donor was somehow Xavier’s identical twin, it makes no sense that he would have an identical spinal cord injury, too.

I wrote up a lengthy diatribe about this subject on my blog, and I included several other continuity issues that nagged at me. How did Magneto get his powers back after losing them in X3? At the end of “The Wolverine,” Trask Industries is just starting construction of the mutant-hunting Sentinels who are the “Days of Future Past” bad guys, but in DOFP, the Sentinel program begins back in the Watergate era. What’s with the 40-year discrepancy?

And as long as we’re ranting, why is Xavier both ambulatory and bald at the start of X3 when he’s paralyzed with a full head of hair at the end of “X-Men: First Class?” I mean, come on! How dumb do they think we are?

After posting a link to this on Facebook, my sister commented, “Holy crud, you’re nerdy.” She’s right; I am. In fact, I’m so nerdy that I’ve actually had some personal experience in this area. I’m writing a young adult novel, and recently my editor pointed out some places in my manuscript where the plot was inconsistent. At first, I didn’t think it was that big a deal. This is my fictional world, after all. Don’t I get to make the rules?

“Yes,” she told me, “you make the rules. And readers will be completely unforgiving if you don’t respect them enough to follow them.”

Those are wise words for nerds and X-Men alike.

Jim Bennett is a recovering actor, theater producer and politico, and he writes about pop culture and politics at his blog, stallioncornell.com.